Electric grain gate control

ABSTRACT

An improved method of operating the gates in grain elevators is disclosed herein. The control device includes, thru electric circuitry, a means of fully controlling and regulating the gate so that it may be stopped at any position between open and closed, with the additional feature of automatically closing the gate in the event of a power failure.

[ Aug. 27, 1974 United States Patent [191 Fitch ELECTRIC GRAINGATECONTROL 2,782,902 2/1957 Sloane......,... ...............318/475 ux[76] Inventor: Otis Fitch, PO. Box 171,Byers, 3283236 Legg Colo. 80103Feb. 4, 1974 [21] Appl. No.: 429,321

Primary Examiner-B. Dobeck [22] Filed:

ABSTRACT An improved method of operating the gates in grain elevators isdisclosed herein. The control device ina means of fully controlso thatit may be stopped g the gate in the eludes, thru electric circuitry,

ling and regulating the gate at any position between open and closed,with the additional feature of automatically closin event of a powerfailure.

[52] US. 318/481, 318/474 [51] Int. Cl. H01h 35/24 [58] Field of Search318/481, 474, 476, 372

[56] References Cited UNITED STATES PATENTS 4 Clains, 4 Drawing Figures2,726,364 12/1955 Merritt................................318/475 Pmmemucevw 3.882.615

SNEH REF 2 ELECTRIC GRAIN GATE CONTROL BACKGROUND OF THE INVENTION Thepresent invention came into being as a result of l a recognized need fora better and more positive means of grain handling and transfer thanthat which is currently employed in grain elevators.

SUMMARY OF THE INVENTION In accordance with the foregoing, it is afeature of the present invention to provide a more positive method ofcontrolling the opening and closing of the grain gate, and including thecapability of stopping the power cycle at any time, which allows thepositive locking of the gate at any chosen point along the vertical pathof travel.

A further feature of the present invention is to equip the gate controlwith a power circuit which will automatically interrupt the current tothe electric motor, closing the gate in the event of either a powerfailure, or of an overload due to jamming the gate on the grain leg.

Other features of this invention will be apparent during the course ofthe following description.

BRIEF DESCRIPTION OF THE DRAWINGS In the accompanying drawings forming apart of this specification, and in which like reference characters areemployed to designate like parts throughout the same:

FIG. 1 is a three-dimensional view of the gate control, illustrating therespective components installed in the cabinet;

FIG. 2 is an orthographic side elevational view of the gate control;

FIG. 3 is an orthographic end view of the gate control; and

FIG. 4 is an electrical schematic view of the control circuit.

DESCRIPTION OF THE PREFERRED EMBODIMENT As shown in FIG. 1, the powernecessary to actuate the lift mechanism is provided by a one-halfhorsepower electric motor 30 which, by mechanical connection thru adrive sprocket 18, a clutch assembly 17, and upper and lower sprocketassemblies 5 and 8; raises the gate lift arm 13 which is attached to thesprocket chain 21 by a gate clamp 12.

A mechanical linkage between the motor 30 and the clutch 17 is providedby the sprocket chain 19, while sprocket chain 20 connects the clutchassembly to the lower sprocket assembly 8.

A sequential description of the gate control mechanism is as follows:

When the handle of the master switch 1 is moved to the ON position, theelectric circuit is energized, supplying power to the circuit breakerswitch 11, the start switch 2, and the relay 3, which energizes thesolenoid 22 which moves the brake mechanism to the ON position.

The brake mechanism which consists of the arm 24, the return spring 25,the bracket 26, the roller 27, the friction belt 28, and the pulley 29,remains engaged until the button on the start switch 2 is depressed,which releases the brake and starts the electric motor,

which, thru the sprocket and chain linkage, raises the gate lift arm 13and the gate itself. As the gate reaches the fully open position, thecam follower 10 on the circuit breaker switch 11 engages the lobe on thecam wheel 9, breaking the circuit, stopping the drive motor and engagingthe brake mechanism, thus locking the drive mechanism and holding thegate in the open position. The gate may be stopped at any point duringthe lifting sequence by releasing the button on the start switch 2.

The gate is closed by turning the master switch 1 to the OFF position,which releases the brake, cuts power to the motor, and allows the gateto descend to the closed position under tension of the compensatingspring 15 and cable 16.

As in the opening cycle, the gate may be stopped at any point during theclosing sequence by turning the master switch 1 to the ON position, thusre-engaging the brake mechanism thru the solenoid 22.

FIGS. 1, 2 and 3 also show the relative positioning of the supportingand attaching components in the cabinet 32, including the relay bracket4, the upper sprocket anchor plate 31, the chain tension adjustmentplate 6 with the adjusting bolts 7, the spring bracket 14, and thesolenoid bracket23.

Referring now to the electrical schematic diagram of FIG. 4,-it is seenthat main switch 1 is provided with electrical contacts 41 and 42,manually operable push button start switch 2 is provided with a pair ofnormally closed stationary contacts 43 and 44 as well as a pair ofnormally open stationary contacts 45 and 46, the pairs of normally openand normally closed contacts adapted to be electrically interconnectedby movable contact arm 47 which is operatively associated with aninsulated member (not shown) which extends exteriorly of the switch andis adapted for manual engagement by an individuals finger for operationof the switch. The relay 3 is shown as having an electric coil 48adapted to operate movable contact arm 49 into and out of contact withthe pair of normally open stationary contacts 50 and 51. The solenoid 22is shown as having a coil 52. The circuit breaker switch 1 l is shown ashaving a pair of normally closed stationary contacts 53 and 54 and apair of normally open stationary contacts 55 and 56, such pairs ofcontacts being electrically interconnectable by a movable contact arm 57which is operatively connected by a stem 58 to the cam follower 10 foroperation by the cam follower between the normally closed and normallyopen position. Contacts 42 and 43 are connected by wire 60, with contact45 being connected to wire 60 by wire 61, contact 44 is connected to oneend of coil 48 by wire 62 with contact 50 being connected to wire 62 bya wire 63, the opposite end of the coil is connected by a wire 63 to awire 64 which is connected to the opposite end 65 of the power source66, contact 51 being connected to the first end of coil 52 by a wire 67with the opposite end of the coil being connected to wire 64 by a wire68. The contact 46 is connected by a wire 69 to a wire 70 to one end ofthe motor 30, the opposite end of the motor being connected by a wire 71to contact 53, with contact 54 being connected by a wire 72 to wire 64.Contact 55 is connected to wire 69 by a wire 73, with contact 56 beingconnectedby a wire 74 to wire 67 intermediate contact 51 and the firstend of solenoid coil 52. The main electrical switch 1 has contact 41connected to an end 40 of the power source 66.

In operation, main switch 1 is closed thus interconnecting contacts 41and 42 effecting the energization of relay coil 48 moving contact arm 49into engagement with contacts 50 and 51 thus energizing solenoid coil 52and applying the brake to the motor. To energize the motor, movable arm47 is depressed thus opening the circuit between contacts 43 and 44 todeenergize the relay coil and associated solenoid coil to release thebrake from the motor, the manual push button effecting the electricalinterconnection of contacts 45 and 46 to energize motor 30 in a mannerto effect the raising of the gate lift arm and the operatively connectedgrain gate, such motor energization being interrupted when the graingate reaches the maximum height as reported by the cam follower actingon the cam disc which effects the opening of the motor circuit by movingthe circuit breaker switch 11 from the normally closed positioninterconnecting contacts 53 and 54, to the normally open position thusinterconnecting contacts 55 and 56 with the effect being thedeenergization of the motor 30 and the energization'of the solenoid 52to apply the brake to the motor thus holding the grain gate in the openposition. This open position is retained upon releasing the manual pushbutton start switch 2 such that it returns to interconnecting contacts43 and 44 as then relay 3 is energized in a manner to retain thesolenoid coil 52 energized to retain the brake applied to the motor. Tolower the grain gate, main switch 1 is opened thus de-energizing thecontrol circuit thus permitting the compensating spring to act againstsprocket chain 21 in a manner to move the sprocket chain in the oppositedirection from when it is driven by the motor so as to lower the graingate, such lowering of the gate returning the circuit breaker switch 11to the normally closed position thus preparing the circuit for furtheroperative energization. It is to be understood that it is possible toretain the grain gate in any desired position between the maximum openand fully closed position by merely energizing the main switch 1 whenthe desired position has been reached, this effecting the energizationof the brake to retain the desired position of the grain gate.

It is to be understood that the form of this invention herewith shownand described is to be taken as a preferred example of the same, andthat this invention is not to be limited to the exact-arrangement ofparts shown in the accompanying drawings or described in thisspecification as various changes in the details of construction as toshape, size, and arrangement of parts may be resorted to withoutdeparting from the spirit of the invention, the scope of the novelconcepts thereof, or the scope of the sub-joined claims.

Having thus described the invention, what is claimed l. A grain gatecontrol intended for the opening and closing of a grain gate such asemployed in grain elevators and the like, comprising an electric motoradapted to be connected .to a suitable power source, a pair ofvertically spaced apart and vertically disposed grain gate sprocketssuitably mounted in a rotatable manner on a frame associated with thegrain gate, a gear train driving mechanism consisting of interconnectedsprockets and sprocket chains having one end drivingly connected to themotor with the opposite end drivingly connected to the bottom most oneof the pair of gate sprockets such that operation of the motor willeffect the simultaneous rotation of the grain gate sprocket, a

vertically extending endless looped sprocket chain extending between thebottom most and top most ones of the gate sprockets, a length of thesprocket chain having a clamping member fixedly attached thereto andprojecting outwardly therefrom for vertical movement therewith alongsuch length of chain between the bottom sprocket and the top sprocket,the projecting member having a clamp at the outermost projecting endthereof adapted to clampingly receive therein a vertically extendinggate lift arm having the bottom portion thereof operatively associatedwith the grain gate such that movement of the arm in a vertically upwarddirection will effect the opening of the grain gate while movement ofthe arm in a vertically downward direction will effect the closing ofthe grain gate, a circular cam disposed adjacent the face of the bottommost gate sprocket on the same shaft therewith and connected to rotatesimultaneously therewith, the circumference of the cam disc having aradially outwardly extending offset circumferal edge portion whichextends outwardly from the center of the cam disc a greater distancethan the remainder of the cam disc, a cam follower having one endadapted to constantly ride against the peripheral circumferal edge orthe cam disc with the opposite end operatively associated with anelectrical circuit breaker type switch such that the cam follower willact to open and close the circuit breaker switch depending upon whetherthe cam follower is engaging the lesser diameter or greater diameterportions of the cam disc, the circuit breaker switch being electricallyconnected with the circuit energizing the motor and operable in a mannerthat when the grain gate is in the maximum open position then the camfollower engages the protruding portion on the cam disc effecting theopening of the switch and the de-energization of the motor, brake meansassociated with the motor and operative upon opening of the circuitbreaker switch to prevent further rotation of the motor, spring meansoperatively associated with the gate sprocket chain in a mannerstretching and tensioning such spring means when the motor is energizedto lift the grain gate, the spring means being effective to operate thegate sprocket chain in the gate closing direction upon thede-energization of the motor and the release of the motor brake means,and an electrical control circuit adapted for controlling all operationsof the opening and closing of the grain gate.

2. The grain gate control as set forth in claim 1 wherein the brakemeans comprises a pully connected on the motor shaft extending outwardlyof the motor opposite from the-end of the motor having the drivesprocket attached thereto, a flexible friction belt in the form of anendless loop having one end loosely engaged on the motor pulley with theopposite end fixedly attached to the grain gate support such that thepulley may loosely rotate within the interior surface of the end of thebelt engaging the pulley, an arm extending parallel to the plane of thefriction belt and spaced outwardly therefrom and having one endpivotally supported to the frame support with the opposite end having aroller joumaled therein and projecting normal thereto, the outermost endof the roller projecting between the legs of the friction belt with theroller being pivotal about its pivot in a manner to engage and disengagethe roller from the friction belt, a spring connected between thepivotable arm and the frame structure adapted to urge the arm into aninoperative position permitting rotation of the motor in the normalmanner, and an electrically operated solenoid having the armaturethereof connected to the top end of the pivotable arm and adapted tomove the arm in a direction opposed to the coil return spring in amanner to engage the roller with the friction belt in a manner totighten the belt about the motor pulley to effectively brake the motorand retain the motor in the braked position as long as the solenoid isenergized, deenergization of the solenoid permitting the coil spring toreturn the arm to the inoperative position permitting normal operationof the motor.

3. The grain gate control as set forth in claim 2 wherein the springmeans associated with the gate sprocket chain for returning the gate tothe closed position comprises a compensating spring having one endfixedly connected to the frame structure with the opposite end connectedto one end of a pulley and cable system having the opposite end of suchcable attached to the opposite length of travel of the sprocket chain ina manner stretching and tensioning the spring when the sprocket chainrotates in a direction to raise the grain gate, with the de-energizationof the motor and brake means permitting the compensating spring to actthrough the pulley and cable system to effect the opposite rotation ofthe sprocket chain about the gate sprocket to effect the verticaldownward movement of the gate arm to effect the closing of thegraingate.

4. The grain gate control as set forth in claim 3 wherein the electricalcircuit control means comprises an electrical source of energy, a mainelectric switch having one end connected to one end of the electricalsource of energy, the opposite end of the main electrical switch beingconnected to a first normally closed contact of a push button typeelectrical switch having a second normally closed contact connected bysuitable electrical wiring to one end of an electromagnetic relay coil,the opposite end of the electromagnetic relay coil being connected tothe remaining'end of the source-of electrical energy, the relay coilhaving a pair of normally open contacts adapted to be closed uponenergization of the relay coil, the brake solenoid being connected inelectrical series relationship with one of to effect the applying of thebrake to the motor, the

manually operable push button switch being provided with a pair ofnormally open contacts, the first of said normally open contacts beingconnected in parallel with the first of said normally closed push buttoncontacts, the second of said normally open push button contacts beingconnected to one end of the motor, the opposite end of the motor beingconnected to a first normally closed contact of the electrical circuitbreaker switch, the second normally closed contact of the circuitbreaker switch being connected to the opposite end of the power sourcesuch that when the circuit is energized the depressing of the manuallyoperated push button will effect the electrical energization of themotor while the circuit breaker switch is in the normally closedposition, the circuit breaker switch having a pair of normally opencontacts, the first of the normally open circuit breaker contacts beingconnected to the first end of the motor, the second of the normally opencircuit breaker switch contacts being connected to the end of thesolenoid connected to the normally open relay contact such that when thegrain gate reaches the maximum open position the cam follower actuatesthe circuit breaker switch from the normally closed to the normally openposition to effect the opening of the motor circuit to de-energize themotor while simultaneously effecting the closing of the normally opencontact to effect the energization of the brake solenoid to apply thebrake to the motor in a manner to retain the gate in the open position,the retention of this open position then being retained by the manuallyoperated push button being released to return to the normally closedposition which maintains the brake solenoid energized, the closing ofthe gate control effected by opening the main electrical switch tode-energi ze the complete control circuit at which time the compensatingspring acting through the pulley and cable system will effect theclosing of the grain gate.

1. A grain gate control intended for the opening and closing of a graingate such as employed in grain elevators and the like, comprising anelectric motor adapted to be connected to a suitable power source, apair of vertically spaced apart and vertically disposed grain gatesprockets suitably mounted in a rotatable manner on a frame associatedwith the grain gate, a gear train driving mechanism consisting ofinterconnected sprockets and sprocket chains having one end drivinglyconnected to the motor with the opposite end drivingly connected to thebottom most one of the pair of gate sprockets such that operation of themotor will effect the simultaneous rotation of the grain gate sprocket,a vertically extending endless looped sprocket chain extending betweenthe bottom most and top most ones of the gate sprockets, a length of thesprocket chain having a clamping member fixedly attached thereto andprojecting outwardly therefrom for vertical movement therewith alongsuch length of chain between the bottom sprocket and the top sprocket,the projecting member having a clamp at the outermost projecting endthereof adapted to clampingly receive therein a vertically extendinggate lift arm having the bottom portion thereof operatively associatedwith the grain gate such that movement of the arm in a vertically upwarddirection will effect the opening of the grain gate while movement ofthe arm in a vertically downward direction will effect the closing ofthe grain gate, a circular cam disposed adjacent the face of the bottommost gate sprocket on the same shaft therewith and connected to rotatesimultaneously therewith, the circumference of the cam disc having aradially outwardly extending offset circumferal edge portion whichextends outwardly from the center of the cam disc a greater distancethan the remainder of the cam disc, a cam follower having one endadapted to constantly ride against the peripheral circumferal edge orthe cam disc with the opposite end operatively associated with anelectrical circuit breaker type switch such that the cam follower willact to open and close the circuit breaker switch depending upon whetherthe cam follower is engaging the lesser diameter or greater diameterportions of the cam disc, the circuit breakeR switch being electricallyconnected with the circuit energizing the motor and operable in a mannerthat when the grain gate is in the maximum open position then the camfollower engages the protruding portion on the cam disc effecting theopening of the switch and the de-energization of the motor, brake meansassociated with the motor and operative upon opening of the circuitbreaker switch to prevent further rotation of the motor, spring meansoperatively associated with the gate sprocket chain in a mannerstretching and tensioning such spring means when the motor is energizedto lift the grain gate, the spring means being effective to operate thegate sprocket chain in the gate closing direction upon thedeenergization of the motor and the release of the motor brake means,and an electrical control circuit adapted for controlling all operationsof the opening and closing of the grain gate.
 2. The grain gate controlas set forth in claim 1 wherein the brake means comprises a pullyconnected on the motor shaft extending outwardly of the motor oppositefrom the end of the motor having the drive sprocket attached thereto, aflexible friction belt in the form of an endless loop having one endloosely engaged on the motor pulley with the opposite end fixedlyattached to the grain gate support such that the pulley may looselyrotate within the interior surface of the end of the belt engaging thepulley, an arm extending parallel to the plane of the friction belt andspaced outwardly therefrom and having one end pivotally supported to theframe support with the opposite end having a roller journaled thereinand projecting normal thereto, the outermost end of the rollerprojecting between the legs of the friction belt with the roller beingpivotal about its pivot in a manner to engage and disengage the rollerfrom the friction belt, a spring connected between the pivotable arm andthe frame structure adapted to urge the arm into an inoperative positionpermitting rotation of the motor in the normal manner, and anelectrically operated solenoid having the armature thereof connected tothe top end of the pivotable arm and adapted to move the arm in adirection opposed to the coil return spring in a manner to engage theroller with the friction belt in a manner to tighten the belt about themotor pulley to effectively brake the motor and retain the motor in thebraked position as long as the solenoid is energized, de-energization ofthe solenoid permitting the coil spring to return the arm to theinoperative position permitting normal operation of the motor.
 3. Thegrain gate control as set forth in claim 2 wherein the spring meansassociated with the gate sprocket chain for returning the gate to theclosed position comprises a compensating spring having one end fixedlyconnected to the frame structure with the opposite end connected to oneend of a pulley and cable system having the opposite end of such cableattached to the opposite length of travel of the sprocket chain in amanner stretching and tensioning the spring when the sprocket chainrotates in a direction to raise the grain gate, with the de-energizationof the motor and brake means permitting the compensating spring to actthrough the pulley and cable system to effect the opposite rotation ofthe sprocket chain about the gate sprocket to effect the verticaldownward movement of the gate arm to effect the closing of the graingate.
 4. The grain gate control as set forth in claim 3 wherein theelectrical circuit control means comprises an electrical source ofenergy, a main electric switch having one end connected to one end ofthe electrical source of energy, the opposite end of the main electricalswitch being connected to a first normally closed contact of a pushbutton type electrical switch having a second normally closed contactconnected by suitable electrical wiring to one end of an electromagneticrelay coil, the opposite end of the electromagnetic relay coil beingconnected to the remaining end of the sOurce of electrical energy, therelay coil having a pair of normally open contacts adapted to be closedupon energization of the relay coil, the brake solenoid being connectedin electrical series relationship with one of the normally open relaycontacts such that manually closing the main electrical switch willeffect the energization of the relay coil to effect the closing of therelay contact to effect the energization of the brake solenoid to effectthe applying of the brake to the motor, the manually operable pushbutton switch being provided with a pair of normally open contacts, thefirst of said normally open contacts being connected in parallel withthe first of said normally closed push button contacts, the second ofsaid normally open push button contacts being connected to one end ofthe motor, the opposite end of the motor being connected to a firstnormally closed contact of the electrical circuit breaker switch, thesecond normally closed contact of the circuit breaker switch beingconnected to the opposite end of the power source such that when thecircuit is energized the depressing of the manually operated push buttonwill effect the electrical energization of the motor while the circuitbreaker switch is in the normally closed position, the circuit breakerswitch having a pair of normally open contacts, the first of thenormally open circuit breaker contacts being connected to the first endof the motor, the second of the normally open circuit breaker switchcontacts being connected to the end of the solenoid connected to thenormally open relay contact such that when the grain gate reaches themaximum open position the cam follower actuates the circuit breakerswitch from the normally closed to the normally open position to effectthe opening of the motor circuit to de-energize the motor whilesimultaneously effecting the closing of the normally open contact toeffect the energization of the brake solenoid to apply the brake to themotor in a manner to retain the gate in the open position, the retentionof this open position then being retained by the manually operated pushbutton being released to return to the normally closed position whichmaintains the brake solenoid energized, the closing of the gate controleffected by opening the main electrical switch to de-energize thecomplete control circuit at which time the compensating spring actingthrough the pulley and cable system will effect the closing of the graingate.